Assessment of optimized conversion of crop residue into bioplastic by response surface methodology: a sustainable approach

The use of commercial plastics is a dilemma due to the pollution caused by its burning, which can cause harm and increase carbon footprints. The solution to these problems is the formation of eco-friendly, inexpensive and easily biodegradable products, including bioplastics. In this study we aimed to prepare bioplastics from agricultural wastes, preferably from banana peels and potato peels. The bioplastic samples were prepared by using water, vinegar, plasticizer (i.e., glycerin) and substrates (i.e., banana and potato peel bioplastics). The results showed that bioplastic prepared from banana peels was thinner and had greater water absorption, swelling percentage and elongation. Regarding biodegradability, potato peel bioplastic took more time than did banana peel bioplastic to biodegrade. Three factors, i.e., water, substrate and plasticizer concentration for elongation as one of the important parameters for bioplastic to prepare, therefore optimization of these parameters was done by central composite design of response surface methodology. Optimized elongation potential of banana peels bioplastic according to model depiction was achieved as 0.4 cm by addition of 53.36 and 2.5 ml of water and a plasticizer concentration, respectively with a substrate concentration of 20 g, after getting optimized elongation further tests including Young’s Modulus, thermal stability and water resistance were performed to test resilience of the bioplastic. Consequently, bioplastic derived from bananas proved to be a more resilient form of plastic which supports banana peels as promising feedstock for bioplastic production.